Still maintained? (Update Dependencies?)

Hi @indexzero 
is this module still maintained?
Do you have plans to update it?
e.g. dependencies: 
[![Dependency Status](https://david-dm.org/indexzero/ps-tree.svg)](https://david-dm.org/indexzero/ps-tree)

Would you accept a PR with tests?
